The Arab World Institute, Paris.
Designed in response to an architectural competition almost 30 years ago, Jean Nouvel's Arabic Institute includes one of my favourite facades.
Uncompromisingly rectangular, the huge south-facing garden courtyard wall has been described as a 60m 'Venetian blind', although its appearance is more Islamic in decorative terms, with a repeating metal motif set behind the glass creating a giant pierced sun-screen.
The motifs are actually 240 motor-controlled apertures, which act like camera diaphragms to create a brise soleil, controlling the light entering the building by reacting and adjusting every hour. The mechanism creates interior spaces with filtered light without allowing harmful rays through to the books within.
Beautiful and practical.
Interior design www.sovibrant.co.uk